Mangets help assemble sophisticated nano structures

Washington, Feb 19 (IANS) Both saturn and flowers possess certain symmetries that are recognisable in the natural world. Now, researchers from Duke and Massachusetts Universities have created a unique set of conditions in which tiny particles within a solution will assemble themselves into these and other complex shapes.

By manipulating the magnetisation of a liquid solution, the researchers have for the first time coaxed magnetic and non-magnetic materials to form intricate nano-structures.

The resulting structures can be “fixed,” meaning they can be permanently linked together.

This raises the possibility of using these structures as basic building blocks for such diverse applications as advanced optics, cloaking devices, data storage and bio-engineering.

Changing the levels of magnetisation of the fluid controls how the particles are attracted to or repelled by one another. By appropriately tuning these interactions, the magnetic and non-magnetic particles form around one another much like a snowflake forms around a microscopic dust particle.

“We have demonstrated that subtle changes in the magnetisation of a fluid can create an environment where a mixture of different particles will self-assemble into complex superstructures,” said Randall Erb, fourth-year graduate student.

He performed these experiments in conjunction with another graduate student Hui Son in the lab of Benjamin Yellen, assistant professor of mechanical engineering and materials science and lead member of the research team, said a Duke release.

The results of the Duke experiments appeared in the Thursday edition of Nature.